This is a follow-on from my recent Chemo & oligometastatic PCa post.
The idea of oligometastatic prostate cancer ("oligo" meaning "few") is that men with a few mets might be treated with radiation &/or surgery & perhaps survival will be extended. But does it make sense to use Taxotere, say, when one has only a few mets?
There were several responses to the post that cast doubt on the concept of oligometastatic disease. So I thought I'd discuss the background.
About 10 years ago, my new urologist (I had just relocated) reassured me that he could keep me alive - "unless you have mets - those guys don't do well." A black & white binary situation. The men who die with PCa rather than of it, were lucky enough to not have mets.
Much later, I asked him about oligometastatic disease, he said that if you have one met, you have a lot - "it's everywhere, you just can't see them."
But when a solitary met at L5 showed up on a bone scan, he put me in touch with a sympathetic radiation-oncologist. Normally, I would have been treated only if I was in pain. The doctor was surprised that I had no pain, & that there was no fracture. I remember thinking - why wait for pain/fracture? The answer, of course, is that it is pointless treating a solitary met if one believes that there must be a dozen or more unseen mets. Where would it stop? You can only have so much radiation.
The oligo topic raises a number of questions that have not really been answered:
1] Do oligometastases represent represent a subclass of PCa, in the same way that two-thirds of Gleason=3+3 cases never progress? Or do all oligo cases progess to many mets?
2] Given the state of PCa imaging technology, how can we be sure that a man has only 3 mets, say?
3] Regardless of whether a man truly has oligo-metastatic disease, is it worth treating him as though he has? e.g. would circulating tumor cells rule out oligo-therapy?
4] Does treatment extend life?
I'll tackle the first question.
...
Do fewer mets indicate less aggressive disease?
The CHAARTED study looked at chemo use up front [1]:
"... the combination of standard ADT and six cycles of docetaxel resulted in significantly longer overall survival than that with standard ADT alone in men with hormone-sensitive metastatic prostate cancer. The clinical benefit ... was more pronounced among patients with a higher burden of disease."
{"Prior studies of chemotherapy plus ADT, which did not show a benefit, were small studies that involved primarily patients with a relatively low tumor burden."}
"the median follow-up was 28.9 months"
It appears that a much longer follow-up would be required for low-volume disease. Why? It seems that low-volume men have better survival anyway.
A Johns Hopkins study [2] (2013) identified the "number of metastases (≤3 versus ≥4; HR 0.50 ...) as one of "four independently prognostic variables for {overall survival}".
A Belgium study [3] (2014) found that "a lower number of metastases at first presentation {was} associated with improved {prostate cancer-specific survival}."
(In this study, the men with only one met & a PSADT>3 months were still alive at 5 years.)
If men who present with oligo-mets have better survival, it looks as though they have a different type of metastatic PCa, that does not progress to multiple mets. If so, it might well be feasible to treat the mets individually.
Here is Dr. Myers:
askdrmyers.wordpress.com/20...
askdrmyers.wordpress.com/20...
-Patrick
[1] nejm.org/doi/full/10.1056/N...
Radiotherapy In The Definitive Management Of Oligometastatic Prostate Cancer
Next step after completed Oligometastatic prostate cancer treatment..
Radiation for Advance Prostate Cancer?
Interesting report on the efficacy of IMRT on prostate cancer
Advanced Metastatic Prostate Cancer
